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import { assertEquals, delay } from "./deps.ts";import {  resolvesNext,  returnsArg,  returnsArgs,  returnsNext,  returnsThis,} from "./callbacks.ts";
Deno.test("returnsThis", () => {  const callback = returnsThis();  const obj = { callback, x: 1, y: 2 };  const obj2 = { x: 2, y: 3 };  assertEquals(callback(), undefined);  assertEquals(obj.callback(), obj);  assertEquals(callback.apply(obj2, []), obj2);});
Deno.test("returnsArg", () => {  let callback = returnsArg(0);  assertEquals(callback(), undefined);  assertEquals(callback("a"), "a");  assertEquals(callback("b", "c"), "b");  callback = returnsArg(1);  assertEquals(callback(), undefined);  assertEquals(callback("a"), undefined);  assertEquals(callback("b", "c"), "c");  assertEquals(callback("d", "e", "f"), "e");});
Deno.test("returnsArgs", () => {  let callback = returnsArgs();  assertEquals(callback(), []);  assertEquals(callback("a"), ["a"]);  assertEquals(callback("b", "c"), ["b", "c"]);  callback = returnsArgs(1);  assertEquals(callback(), []);  assertEquals(callback("a"), []);  assertEquals(callback("b", "c"), ["c"]);  assertEquals(callback("d", "e", "f"), ["e", "f"]);  callback = returnsArgs(1, 3);  assertEquals(callback("a"), []);  assertEquals(callback("b", "c"), ["c"]);  assertEquals(callback("d", "e", "f"), ["e", "f"]);  assertEquals(callback("d", "e", "f", "g"), ["e", "f"]);});
Deno.test("returnsNext with array", () => {  let results: number[] = [1, 2, 3];  let callback = returnsNext(results);  assertEquals(callback(), 1);  assertEquals(callback(), 2);  assertEquals(callback(), 3);  assertEquals(callback(), undefined);
  results = [];  callback = returnsNext(results);  results.push(1, 2, 3);  assertEquals(callback(), 1);  assertEquals(callback(), 2);  assertEquals(callback(), 3);  results.push(4);  assertEquals(callback(), 4);  assertEquals(callback(), undefined);  results.push(5);  assertEquals(callback(), undefined);});
Deno.test("returnsNext with iterator", () => {  let results: number[] = [1, 2, 3];  let callback = returnsNext(results.values());  assertEquals(callback(), 1);  assertEquals(callback(), 2);  assertEquals(callback(), 3);  assertEquals(callback(), undefined);
  results = [];  callback = returnsNext(results.values());  results.push(1, 2, 3);  assertEquals(callback(), 1);  assertEquals(callback(), 2);  assertEquals(callback(), 3);  results.push(4);  assertEquals(callback(), 4);  assertEquals(callback(), undefined);  results.push(5);  assertEquals(callback(), undefined);});
Deno.test("returnsNext with generator", () => {  let results: number[] = [1, 2, 3];  const generator = function* () {    yield* results;  };  let callback = returnsNext(generator());  assertEquals(callback(), 1);  assertEquals(callback(), 2);  assertEquals(callback(), 3);  assertEquals(callback(), undefined);
  results = [];  callback = returnsNext(generator());  results.push(1, 2, 3);  assertEquals(callback(), 1);  assertEquals(callback(), 2);  assertEquals(callback(), 3);  results.push(4);  assertEquals(callback(), 4);  assertEquals(callback(), undefined);  results.push(5);  assertEquals(callback(), undefined);});
Deno.test("resolvesNext with array", async () => {  let results: number[] = [1, 2, 3];  let callback = resolvesNext(results);  const value = callback();  assertEquals(Promise.resolve(value), value);  assertEquals(await value, 1);  assertEquals(await callback(), 2);  assertEquals(await callback(), 3);  assertEquals(await callback(), undefined);
  results = [];  callback = resolvesNext(results);  results.push(1, 2, 3);  assertEquals(await callback(), 1);  assertEquals(await callback(), 2);  assertEquals(await callback(), 3);  results.push(4);  assertEquals(await callback(), 4);  assertEquals(await callback(), undefined);  results.push(5);  assertEquals(await callback(), undefined);});
Deno.test("resolvesNext with iterator", async () => {  let results: number[] = [1, 2, 3];  let callback = resolvesNext(results.values());  const value = callback();  assertEquals(Promise.resolve(value), value);  assertEquals(await value, 1);  assertEquals(await callback(), 2);  assertEquals(await callback(), 3);  assertEquals(await callback(), undefined);
  results = [];  callback = resolvesNext(results.values());  results.push(1, 2, 3);  assertEquals(await callback(), 1);  assertEquals(await callback(), 2);  assertEquals(await callback(), 3);  results.push(4);  assertEquals(await callback(), 4);  assertEquals(await callback(), undefined);  results.push(5);  assertEquals(await callback(), undefined);});
Deno.test("resolvesNext with async generator", async () => {  let results: number[] = [1, 2, 3];  const asyncGenerator = async function* () {    await delay(0);    yield* results;  };  let callback = resolvesNext(asyncGenerator());  const value = callback();  assertEquals(Promise.resolve(value), value);  assertEquals(await value, 1);  assertEquals(await callback(), 2);  assertEquals(await callback(), 3);  assertEquals(await callback(), undefined);
  results = [];  callback = resolvesNext(asyncGenerator());  results.push(1, 2, 3);  assertEquals(await callback(), 1);  assertEquals(await callback(), 2);  assertEquals(await callback(), 3);  results.push(4);  assertEquals(await callback(), 4);  assertEquals(await callback(), undefined);  results.push(5);  assertEquals(await callback(), undefined);});